ECHINOCHASMUS, NEW SPECIES (TREMATODA: ECHINOSTOMATIDAE) FROM EGYPT.

In this study a new species of Echinochasnius (Dietz, 1909) is recorded for the first time in Egypt. Life cycle of one of gymnocephalous cercariae procured from Melanoides tuberculata snail was successfully completed in the laboratory. A total of 407 Melanoides tuberculata snails were collected from Mansouriya Canal, Giza Governorate. They were individually exposed to artificial light to determine natural infection with trematode larvae, Seven snails were found infected with gymnocephalous cercariae (infection index of 1.71). These cercariae were used to infect Gambusia affinis fish as second intermediate host. The infected gills were given to clean laboratory bred Rattus norvegicus as experimental final host. Adult worms were obtained ten days post-infection from rats' intestine identified as Echinochasmus after accurate comparson with standard keys. The diagnostic morphology of developmental stages were given.